There is a conventionally known radiation detector (radiation detection element) in which a scintillator layer of a columnar crystal structure is formed on a sensor panel (light receiving unit), as described in Patent Literature 1 below. In this radiation detector, a plurality of bonding pads electrically connected to light receiving elements are arranged outside the light receiving unit. When viewed from a stacking direction of the scintillator layer, a resin frame is formed so as to pass between the scintillator layer and the bonding pads and surround the scintillator layer. The scintillator layer is covered by a moisture-resistant protection film and the outer edge of the moisture-resistant protection film lies onto the resin frame.
Radiation detection devices with such a radiation detector are in demand as portable devices, in addition to stationary devices. Accordingly, there is a need for reduction in size and weight of the radiation detection devices. For this reason, the radiation detector forming the radiation detection device is required to reduce its size and weight. For reducing the size of the radiation detector, it is preferable to make the size of the resin frame as small as possible and the distance between the resin frame and the outer edge of the scintillator layer as short as possible, thereby maximizing the area of the scintillator layer (effective area) in the region inside the resin frame.